Vapor discharge device



J C. READ VAPOR DISCHARGE DEVICE Filed Jan. 18, 1929 Inventor. YJ'ohn.C.FQea.ci. W 2

- Hie Attorneg Patented Jan. 26, 1932 UNITED STATES CORPORATION OF NEWYORK VAPOR mscnensn DEVICE H Application filed January 18, 1929, SerialNo. 333,261, and in Great Britain February 16, 1928.

My invention relates to vapor discharge devices such as mercury arcrectifiers for ex-- ample, and has for its principal object theprovision of an improved means whereby the r vacuum chamber of thedevice may be effectively evacuated during operation.

In mercury arc rectifiers, if the connecting pipe leading from theVacuum chamber to the evacuating pump is placed at the centre of thechamber, then there is risk that air may be trapped in the corners ofthe chamber near the anodes; and if the pipe is placed near the anodesair is trapped at the centre of the tank; since in both cases theviolent J blast of mercury vapor issuing from thecathode duringoperation tends to drive air before it into the various pockets in thechamher, and thereby prevent it from being evacuated by the pump. It isundesirable to provide several pipes from the vacuum chamber to the pumpto eliminate this trouble, on

account of the complication and dificulty of making vacuum-tlght Jomts.I

The present inventlon consists in connecting the evacuating pipe of thevacuum pump.

leading to the vacuum pump is shown at the centre of the vacuum chamber.It is found that with this position of the evacuating pipe there issometimes a tendency for air to be trapped by the mercury vapor blast atthe rim 6 of the tank and this cannot be prevented by attaching theevacuating pipe at 6 because in that case air is sometimes trapped inthe centre of the tank instead. Internal ducts or pipes 7 are thereforeprovided leading to the pipe 5 from points where air may be expected tobe trapped.

In this Way air is drained away from any pockets in the vacuum chamberwithout being influenced by the blast of mercury vapor,

r was.

JOHN G. READ, or RUGBY, ENGLAND, ASSIGNOR T GENERAL ELncrnIc COMPANY, n

and at the same time, since these drain pipes.

are entirely insidethe vacuum chamber, no additional vacuum-tightjointsare required.

In arranging such internal air drain ducts it is desirable to malre thecoolest part-of the duct be the end which is adjacent Y to theevacuating pipe; This insures that any flow of mercury vapor which takesplace along the duct will. bein the direction to help the air flow topipe rather than ina direction to I it might be expected to collect.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A vapor discharge device including an evacuated vessel, an exhaustpipe attached thereto and opening into the upper portion of said vesselto drain air from said portion,

and a second pipe located within said vessel extending into the end ofsaid exhaust pipe from another point within said vessel to drain airinto said exhaust pipe from another portion of said vessel.

2. A'Vapor discharge device including an evacuated vessel, an exhaustpipe attached thereto and opening into the upper portion of said vesselto drain air from said portion, and a plurality of ducts within saidvessel opening into the end of said pipe and leading from said pipe toseparate points within said vessel to drain air into said exhaust pipefrom other portions of said vessel.

3. A vapor discharge deviceincluding an evacuated vessel, an exhaustpipe attached thereto, a plurality of pipes extending from separatepoints within said vessel into the end of said pipe, and means forcooling said evacuating pipe.

4. A vapor discharge device including an evacuated vessel provided Withanode chambers, an exhaust pipe attached to said vessel, and means forevacuating said anode chamhers including a plurality of pipes withinsaid vessel and extending from said anode chambers into the mouth ofsaid exhausting p A vapor discharge device including an evacuatedvessel, an exhaust pipe attached thereto, and a plurality of ductsWithin said vessel leading from separate points therein and extendinginto the end of said exhaust pipe.

6. A vapor discharge device including an evacuated vessel, an exhaustpipe attached to said vessel, and a plurality of pipes mounted Withinsaid vessel and leading respectively to said exhaust pipe from pointsWithin said vessel at which air tends to collect.

7. A vapor discharge device including an evacuated vessel, an exhaustpipe attached to said vessel at a point at Which air tends to collect,and a plurality of ducts Within said vessel and leading respectively tosaid exhaust pipe from other points Within said vessel at which airtends to be trapped, to cause said trapped air to be evacuated by 25said exhaust pipe.

In Witness whereof, I hereunto set my hand, this 1st day of January,1929.

JOHN C. READ.

